A machine tool tends to consume a very large amount of electric power when a tool and a workpiece are moved relative to each other, i.e. when a positioning and feeding motion is performed, compared to other cases. Accordingly, in a facility such as a factory in which multiple machine tools are installed, a large peak occurs in an electric power consumption of the facility when the timings of positioning and feeding motion of these machine tools coincide with each other. As a result, a large load is placed on a power supply system of the facility.
In this respect, for example, Patent Document 1 listed below and the like proposes a processing machine including a mode changing switch allowing the processing machine to change from a normal mode to an energy saving mode and vice versa. An operator can set the mode changing switch to the energy saving mode as needed and thereby reduce the required current to deal with the large peak.